Oracle
A service that provides external real-world data to smart contracts on the blockchain. Oracles bridge the gap between on-chain and off-chain data.
Why It Matters
Oracles act as bridges between blockchain networks and real-world data, providing essential information needed for smart contracts to function properly. They expand the capabilities of blockchains, enabling them to interact with the outside world.
Example
For example, a weather oracle can provide weather data to a smart contract that pays out if it rains, enabling decentralized applications to operate based on real-world conditions and events.
Beginner Context
For those new to the crypto space, understanding oracles can open up new possibilities in decentralized applications and finance. They illustrate how blockchains can integrate external information, enhancing their functionality.
Mike Starr
Founder, CryptoWizardTools · M.S. Organizational Management
Last reviewed: August 2026
Related Terms
Liquidity Pool
A collection of funds locked in a smart contract that provides liquidity for decentralized exchanges. Users who contribute to pools earn trading fees as rewards.
Hard Fork
A major change to a blockchain protocol that is not backward-compatible. Nodes that do not upgrade to the new rules are rejected by the new chain, sometimes creating two separate blockchains. Bitcoin Cash was created via a hard fork of Bitcoin.
51% Attack
An attack on a blockchain where a single entity gains control of more than 50% of the network's mining or validation power, allowing them to rewrite transactions, double-spend, or censor blocks. The more decentralized a network, the harder this is to execute.
CEX
Centralized Exchange. A cryptocurrency trading platform operated by a centralized company that acts as an intermediary between buyers and sellers.
Block Reward
The amount of cryptocurrency awarded to a miner or validator for successfully adding a new block to the blockchain. In Bitcoin, the block reward is halved approximately every four years in an event called the halving.